1. Field of the Invention
The present invention relates to a touch panel, more particularly to a touch panel capable of ensuring good optical performance of a touch screen comprising the same.
2. Description of the Prior Arts
With the advance of technology, researches on integrating a touch panel with a display panel are conducted for developing a touch screen having good optical performance and convenience in use, so as to apply the touch screen on various electronic devices such as cell phones, digital cameras, televisions or computers.
A touch panel generally includes a touch region and a non-touch region surrounding the touch region. A frame made of an opaque material is disposed in the non-display region to cover the wiring pattern electrically connected with the sensing electrodes. Accordingly, during operation the user only see items in the display region, i.e. a touch operation region, such that a touch screen of the touch panel has a clear appearance.
With reference to FIG. 4, a touch panel 4 in the art includes a transparent substrate 41, a sensing electrode layer 42, an insulated ink layer 43, a conductive layer 44 and a wiring layer 45. The touch panel 4 is divided into a display region 46 and a non-display region 47 by the insulated ink layer 43. The conductive layer 44 is disposed on both the sensing electrode layer 42 and the insulated ink layer 43, and the wiring layer 45 is disposed on both the insulated ink layer 43 and the conductive layer 44, such that the wiring layer 45 is electrically connected with the conductive layer 44 and the sensing electrode layer 42 for signal transmission.
With the low transmittance of light, the conductive layer 44 disposed at the interface between the display region 46 and non-display region 47 not only reduces the transmittance in the display region 46, but also produces many yellow spots in the display region 46 near the interface, such that the optical performance of a touch screen is deteriorated.